Abstract 15202: Clinic BP During Follow Up is as Useful as Ambulatory Blood Pressure in Predicting Stroke
Background: Ambulatory BP (ABP) has been reported to be a better marker than clinic BP in predicting future incidence of stroke. However, most of the studies which compared clinic BP vs. ABP adopted only a few clinic BP readings at baseline as clinic BP values.
Objectives: We aimed this study to compare ABP at baseline and mean of all clinic BP readings during the follow-up visits.
Methods: We enrolled 457 hypertensives, and performed ABP monitoring at baseline. All the clinic BP readings during the follow up were picked up from the medical records. The mean age of the subjects was 67.0 ± 9.2 years, and they were followed for 66 ± 27 months. Stroke was defined as an outcome. Clinic BP was measured monthly by a standard method (measured three times after a 5-min rest; the 2nd and 3rd readings was averaged and expressed as “mean clinic BP”). Multivariable Cox regression analyses were performed adjusting for age, sex, BMI, diabetes, creatinine, and smoking.
Results: In multivariate Cox regression analyses, the hazard ratios (HR) for each 10-mmHg increase in BP level were highest in the “mean clinic SBP” (HR=1.76, 95% CI 1.29-2.39, P<0.001), followed by 24-hour SBP (HR=1.47, 1.19-1.80, P<0.001), awake SBP (HR=1.39, 1.14-1.69, P=0.001), and sleep SBP (HR=1.32, 1.10-1.58, P=0.002). These relationships remained significant after further adjustment of ABP levels (Figure). However, the baseline clinic SBP was not associated with stroke events (HR=1.17, 0.98-1.41, P=0.09).
Conclusion: In addition to ABP values, the mean of all clinic SBP values during the follow-up period were robust and important predictors of stroke events in routine clinical practice. These results imply that carefully-measured clinic BP during follow-up visits is important for risk stratification of future stroke events.
- © 2012 by American Heart Association, Inc.